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G Verschraegen

Publications and source records attributed to G Verschraegen.

At least 55 records · Page 3Linked to original sources

Evaluation of the applicability of amplified rDNA-restriction analysis (ARDRA) to identification of species of the genus Corynebacterium.

The 16S rRNA genes (rDNA) of 50 strains belonging to 26 different coryneform bacterial species and genomospecies and of the type strain of Rhodococcus equi were enzymatically amplified. Amplified rDNA restriction analysis (ARDRA) with the enzymes AluI, CfoI and RsaI was carried out. The combination of the ARDRA patterns obtained after restriction with these three different enzymes enabled the differentiation between the following species: Corynebacterium accolens (number of strains = 2), C. afermentans subsp. afermentans (2), C. afermentans subsp. lipophilum (2), C. amycolatum (3), CDC coryneform group ANF-1-like (1), CDC coryneform group ANF-3-like (1), C. cystitidis (1), C. diphtheriae (4), C. jeikeium (3), C. macginleyi (2), C. minutissimum (1), C. pilosum (1), C. pseudotuberculosis (2), C. renale (2), C. striatum (2), C. urealyticum (3), C. xerosis (1), CDC coryneform groups B-1 (2), B-3 (2), F-1, genomospecies 1 and 2 (6), G, genomospecies 1 (1) and G, genomospecies 2 (2). The following strains or species could not be differentiated from each other: C. pseudodiphtheriticum (2) from C. propinquum (former CDC coryneform group ANF-3) (2), CDC coryneform group F-1, genomospecies 1 (4) from genomospecies 2 (2) and C. jeikeium genomospecies A (1) from genomospecies C (2). ARDRA may represent a possible alternative for identification of coryneforms, since this technique enabled the identification of most coryneforms tested and since DNA extraction (i.e. cell lysis by boiling), amplification, restriction and electrophoresis can be carried out within 8 hours. This might allow quick identification of C. diphtheriae and other possible pathogens of the genus Corynebacterium.

Corynebacterium↗

Treatment of Clostridium difficile colitis. Summary of a round table held in Brussels on March, 3rd, 1994.

Due to the growing incidence and the severity of infections due to vancomycin resistant enterococci, it is now recommended to treat mild to moderate cases of Clostridium difficile-associated diarrhoea with metronidazole while maintaining the use of oral vancomycin in serious or life-threatening colitis. Clostridium difficile is a common cause of diarrhoea after antibiotic therapy and induces a spectrum of diseases ranging from mild diarrhoea to pseudomembranous colitis (PMC). It is considered to be the first cause of diarrhoea occurring among hospitalized patients (1).

Clostridioides difficile↗

Identification of Acinetobacter genomic species by amplified ribosomal DNA restriction analysis.

A total of 53 field and reference strains, including the type strains of the seven named species (nomenspecies) and belonging to the 18 described genomic species (DNA groups) of the genus Acinetobacter, were studied by amplified ribosomal DNA restriction analysis (ARDRA). Restriction analysis with the enzymes AluI, CfoI, MboI, RsaI, and MspI of the enzymatically amplified 16S rRNA genes allowed us to identify all species except the genomic species 4 (Acinetobacter haemolyticus) and 7 (A. johnsonii), 5 (A. junii) and 17, and 10 and 11, which clustered pairwise in three respective groups. Further analysis with the enzyme HaeIII, HinfI, NciI, ScrFI, or TaqI did not allow us to differentiate the species within these three clusters. However, use of a few additional simple phenotypic tests (hemolysis, growth at 37 degrees C, production of acid from glucose, and gelatin hydrolysis) can be used to differentiate between the species within these clusters. ARDRA proved to be a rapid and reliable method for the identification of most of the Acinetobacter genomic species, including the closely related DNA groups 1 (A. calcoaceticus), 2 (A. baumannii), 3, and 13. The results of this study suggest that ARDRA can be used for the identification of Acinetobacter species and as such may help to elucidate the ecology and clinical significance of the different species of this genus. Since ARDRA uses universal 16S rRNA gene primers, it is expected to be applicable to the identification of most bacterial species. Furthermore, ARDRA is less prone to contamination problems than PCR for detection, since the use of cultured organisms results in a large initial quantity of target DNA.

Acinetobacter↗

Case of recurrent Flavimonas oryzihabitans bacteremia associated with an implanted central venous catheter (Port-A-Cath): assessment of clonality by arbitrarily primed PCR.

Flavimonas oryzihabitans bacteremias, which occurred immediately after the flushing or use of an implanted central venous catheter (Port-A-Cath) in two patients at the same pediatric ward, were studied by arbitrarily primed PCR. We conclude that the colonization of the Port-A-Cath with F. oryzihabitans described here lasted for several months.

Bacteremia↗

Study of the influence of plasmids on the arbitrary primer polymerase chain reaction fingerprint of Escherichia coli strains.

To study the effect of plasmids on the arbitrary primer-polymerase chain reaction fingerprint of bacterial strains, the Escherichia coli strains DH5, Top10, and W3110 were transformed with plasmids of different sizes: respectively, pUC19, pCEP and two clinically important plasmids carrying resistance to several antibiotics. Total DNA, i.e. both chromosomal and plasmid DNA, was prepared from transformed cells by boiling the cell suspensions and by phenol-chloroform extraction; chromosomal DNA was prepared by the same methods from the non-transformed, plasmid-free strains; plasmid DNA of pUC19 was purchased; plasmid DNA of pCEP was purified from the transformed strains by caesium chloride density gradient centrifugation. Arbitrarily primed polymerase chain reaction was carried out for all of these preparations. Amplification carried out independently with three different primers resulted in similar patterns for the chromosomal preparations whether or not plasmid was present. Amplification of plasmid DNA gave different patterns, characterized by fragments larger than those obtained when total or chromosomal DNA were used as the target. These data illustrate that the plasmids studied here do not influence the chromosomal arbitrarily primed PCR fingerprint, although plasmids alone are amplified in the absence of chromosomal DNA. Experiments comparing different relative concentrations of plasmid and chromosomal DNA indicate that under natural conditions the amount of chromosomal DNA per cell is sufficient to inhibit observable amplification of the plasmid(s) present.

Base Sequence↗

Bronchopneumonia caused by Propionibacterium acnes.

Propionibacterium acnes was identified as the pathogen in a case of subacute lung infection by examination of an open lung biopsy specimen. The patient was a 65-year-old male with exacerbation of chronic lung disease. The organism was isolated in pure culture and was present in large numbers on Gram stain. Histological examination demonstrated active interstitial fibrosis; macrophages laden with Propionibacterium acnes antigen were revealed using a peroxidase-antiperoxidase stain. This is the first report of subacute infection of pulmonary tissue due to this organism.

Aged↗

Pseudomonas aeruginosa serotype O12 outbreak studied by arbitrary primer PCR.

A total of 16 colonizing and infecting ofloxacin-resistant Pseudomonas aeruginosa strains and two strains isolated from ventilation equipment fluids, all with similar colonial morphologies and with minor but distinct susceptibility differences, were suspected of belonging to a single outbreak and were studied by arbitrary primer (AP) PCR. Thirteen nonrelated strains were included to evaluate the discriminatory capacity of the technique. AP PCR fingerprinting was compared with serotyping, phage typing, and antibiotic susceptibility testing. AP PCR was performed independently with three different primers. The different AP PCR typing systems yielded almost identical patterns for the epidemic strains and enabled us to differentiate most of the nonrelated strains from each other and from the outbreak strains. The combination of AP PCR typing and the phenotyping techniques that we used enabled us to conclude that an outbreak was occurring. In general, the typeability of AP PCR was greater than those of phage typing and serotyping, while the discriminatory powers of the three methods were comparable.

Bacterial Typing Techniques↗

Bacterial surveillance cultures in a geriatric ward.

A study was carried out to examine the prevalence of oropharyngeal and urinary tract colonization and to compare the colonizing bacteria with the strains causing nosocomial infections during patients' stays in a geriatric ward. Colonization with Gram-negative rods was not uncommon. Nosocomial infections frequently occurred, although colonization seldom resulted in infection. Ampicillin and co-trimoxazole resistance was common in Gram-negative rods. There was little resistance to tobramycin, temocillin and quinolones in strains isolated in patients admitted from home or a nursing home. Isolates resistant to these antibiotics were found in patients admitted from other departments of the hospital, especially from the intensive care unit or during prolonged stay in the ward. Routine cultures for colonization were not predictive for subsequent infection. However, continuous monitoring of Gram-negative rods in colonization and infection remains an important instrument for a preventive policy and to guide antibiotic treatment.

Aged↗

Polyphasic taxonomy leading to the proposal of Moraxella canis sp. nov. for Moraxella catarrhalis-like strains.

The taxonomic position of a group of 16 Moraxella catarrhalis-like strains, isolated mainly from dogs, was examined by using morphological tests, biochemical tests, serology, ribotyping with oligonucleotide probes, polymerase chain reaction typing of the 16S rRNA gene and the 16S-23S rRNA gene spacer region, polyacrylamide gel electrophoresis of total proteins, fatty acid profiles, moles percent G+C, dot spot and in-solution DNA-DNA hybridizations, and DNA-rRNA hybridizations. It was found that these organisms constitute a distinct cluster within the genus Moraxella. Since they differ genotypically as well as phenotypically from previously described Moraxella species, a new species, Moraxella canis, is proposed to accommodate these isolates. The type strain is LMG 11194 (= N7 = CCUG 8415A).

Animals↗

Identification of Mycobacterium species by using amplified ribosomal DNA restriction analysis.

A rapid procedure for the identification of cultured Mycobacterium isolates, based on the combination of enzymatic amplification and restriction analysis, is described. The 16S rRNA genes (rDNA) of 99 strains belonging to 18 different species of the genus Mycobacterium were enzymatically amplified. Amplified rDNA restriction analysis with the enzymes CfoI, MboI, and RsaI was carried out. The combination of the amplified rDNA restriction analysis patterns obtained after restriction with CfoI and MboI enabled differentiation between Mycobacterium asiaticum (number of strains = 4), M. avium (n = 22), M. chelonae (n = 5), M. flavescens (n = 1), M. fortuitum (n = 6), M. gordonae (n = 6), M. intracellulare (n = 13), M. marinum (n = 7), M. nonchromogenicum (n = 1), M. simiae (n = 5), M. terrae (n = 5), the M. tuberculosis complex (n = 11), and 2 of 4 strains of M. xenopi. Further restriction with RsaI was necessary to differentiate between the species M. kansasii (n = 5), M. scrofulaceum (n = 4), and the 2 other M. xenopi strains. The M. avium-M. intracellulare complex was characterized by a specific MboI pattern, and M. avium and M. intracellulare strains could further be differentiated by restriction with CfoI. The whole procedure, including sample preparation prior to the polymerase chain reaction, can be carried out within 8 h, starting from a pure culture.

Base Sequence↗

Effect of penicillin on the clinical course of streptococcal pharyngitis in general practice.

The aim of the study was to explore whether penicillin was superior to placebo in altering the clinical course of proven streptococcal pharyngitis. A randomised, parallel, double blind placebo controlled trial of 10 days duration was undertaken in 42 general practices in the Gent region (Flemish part of Belgium). Phenoxymethylpenicillin (adults 250 mg t.i.d. and children 125 mg t.i.d.) or placebo were administrated to 173 patients, aged 5 to 50 y, with acute sore throat and a positive culture for Group A beta-haemolytic streptococci. Penicillin and placebo tablets were identical. Patient compliance was monitored by assay of penicillin in urine (Sarcina lutea method). The primary outcome variable was sore throat as recorded by the physician on Day 3. The experiences of the patients themselves over the 10 day period were also assessed. Secondary outcome variables were other local and general symptoms and signs of streptococcal throat infection. In the penicillin group on Day 3, 23.2% of the patients still complained of sore throat versus 65.9% in the placebo group: difference 42.7% (C.I. 29.4%, 56.1%). This finding was confirmed by survival analysis of the symptom 'sore throat', as recorded by the patients. The physicians recorded on Day 3 a significant positive effect on another symptom (malaise: P < 0.04) and certain clinical signs (abnormal throat: P < 0.07; and redness of throat: P < 0.003). Penicillin had more adverse effects than placebo (P < 0.007). It also inhibited the rise in ASLO (P < 0.001). In this study in general practice, penicillin had a slight but definitive positive effect on the clinical evolution of streptococcal pharyngitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Septicemia with Ewingella americana.

Ewingella americana was isolated from two blood cultures from a 75-year-old male after cholecystectomy. The characteristics of this strain are compared with the reported biochemical characteristics of 44 American strains. Previously described infections and pseudoinfections with E. americana are reviewed.

Aged↗

Selective streptococcal agar versus blood agar for detection of group A beta-hemolytic streptococci in patients with acute pharyngitis.

In a study on acute pharyngitis in general practice, we compared a selective group A streptococcal agar (ssA) for the recovery of group A beta-hemolytic streptococci (GABHS) with sheep blood agar. All plates were incubated at 36 degrees C in an atmosphere reinforced with 5% CO2 for 48 h with a first reading after 24 h. A total of 197 GABHS isolates were obtained from 721 throat cultures on both media. The recovery of GABHS was significantly higher after 48 h of incubation for both media. With the ssA plate, we detected significantly more GABHS after 24 h as well as after 48 h of incubation. The ssA plate reduced normal flora qualitatively and quantitatively. In conclusion, ssA is more sensitive and specific for the detection of GABHS than sheep blood agar and moreover easier to read. We recommend incubation for 48 h.

Agar↗

Respiratory tract carrier rates of Moraxella (Branhamella) catarrhalis in adults and children and interpretation of the isolation of M. catarrhalis from sputum.

Nonselective media and previously described selective media were used to study the occurrence of Moraxella (Branhamella) catarrhalis in sputum samples of good and poor quality and in samples taken from different sites of the upper respiratory tracts of healthy subjects. It was found that in healthy adults the carrier rate was 5.4%, as opposed to 50.8% in children and 26.5% in people older than 60 years. M. catarrhalis was recovered significantly more often from sputum samples of good quality (5%) than from poor quality samples (0.5%), and when present, it was found mostly in the presence of high inocula. From these data gathered from healthy and diseased subjects, it is concluded that the presence of M. catarrhalis in the sputum of adults is rarely due to oronasopharyngeal contamination of the sputum. Similar findings reported by others are discussed, and the origins of the currently held concept that M. catarrhalis is a common commensal organism of the human upper respiratory tract are traced.

Adult↗

Serological typing of Branhamella catarrhalis strains on the basis of lipopolysaccharide antigens.

A total of 302 strains of Branhamella catarrhalis from different parts of the world were serologically typed according to their lipopolysaccharide (LPS) antigenicity. For this purpose, an inhibition enzyme-linked immunosorbent assay was developed using the following reagents: antisera raised against whole bacterial suspensions for a panel of 16 serotype strains and LPS prepared from these strains by phenol extraction. Antisera were absorbed with whole bacterial suspensions of the B. catarrhalis strains to be tested. The residual activity of the sera against the homologous LPS was determined by means of an enzyme-linked immunosorbent assay, using microdilution plates coated with LPS. Strains which gave greater than 90% reduction of activity were considered to carry the same LPS type as the serotype strain. It was shown that 93.4% of the strains tested carried one of three possible LPS types. LPS of B. catarrhalis are the rough type and have an apparent Mr of 5,500, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Antigens, Bacterial↗

Flucloxacillin compared with cefazolin in short-term prophylaxis for clean orthopedic surgery.

Two-hundred and fifty-two patients were included in a prospective, randomized, double-blind trial comparing the efficacy of flucloxacillin with that of cefazolin for clean orthopedic surgery. The preventive antibiotic regimen consisted of three 1-g injections perioperatively. There were 126 patients in each group, and the follow-up period was at least 6 months. Two deep (1.6%) and five superficial (4.0%) infections occurred in the flucloxacillin group. Three deep (2.4%) and five superficial (4.0%) infections developed in the cefazolin group.

Adolescent↗